Sieve or chaffer



Jai. 1, 1946.

E. G. wAn'E SIEVE OR CHAFFER Filed Feb. 6, 1942 EHNEST w /MM gimme/WM W HJTE Patented Jan. 1, 1946 SIEVE OR CHAFFER Ernest G. Waite, Jackson, Mich., assignor, by mesne assignments, to Hart-Carter Company, Peoria, Ill., a corporation of Delaware Application February 6, 1942, Serial No. 429,719

3 Claims.

The present invention relates to screens, sieves, and chaffers, particularly of the adjustable type formed by metal slats.

In devices of the aforesaid type used in combines and threshers, the grain and air capacity, durability, adaptability to cleaning, and freedom from clogging are characteristics of major importance.

Devices according to the present invention, when adjusted into an open position, present a saw tooth surface which materially assists in the advancement of the straw and chaif upon vibration and under the influence of the air flow. When closed, similar adjacent surfaces of the metal slats collectively form a relatively rigid, durable surface free from protuberances, adapted to be broken or disturbed in service or upon Cleaning. These same surface portions of the slats when in adjusted position confine and direct the air fiow through the adjustable openings or apertures. The slat construction deflning the adjustable openings in two of the forms of the illustrated invention is stifiened in all directions and offers transverse support to straw and chaff, preventing the same from passing through the adjusted area sideways.

Thus, the object of the present invention is found in the provision of improvements in sieve, screen and chafier construction having the aforesaid structural characteristics and advantages, as well as in the combination, arrangement and construction of parts more specifically set forth hereinafter.

In the drawing, wherein three different forms of the invention are illustrated,

Fig. 1 is a fragmentary perspective view of a section of a sieve or chaifer embodying the present invention with the slats shown fully opened,

Fig. 2 is an end view of the slats shown in Fig. 1 but in a closed position, the open position being shown in dotted Outline,

Fig. 3 is a view similar to Fig. 1 of a slightly modified form of sieve or chafier with the slats shown closed,

Fig. 4 is a view similar to Fig. 3 of a modified form of slat, and

Fig. 5 is a sectional view taken on line V-V of Fig. 4 of an aperture finger or detent.

Referring to Figs. 1 and 2, the sieve, screen or i chaffer section shown comprises a plurality of slats IO of angular elongated shapes supported for adjustment upon rods |2 in a well known manner. Each slat IO has a plain top portion M, a tail IS with apertures IB, and a turn fiange 20.

i With the slats IO adjusted to their full open position, the edges 22 engage the fianges 20 with the latter acting as an adjustment stop as well as supporting the portions Ill along the edges 22. The fianges 20 also serve to seal the space between adjacent slats IO with the slats in full open position, which directs more of the air fiow through the opening IB and at a higher Velocity vthan would otherwise be the case.

The saw tooth contour of the sieve in all positions of adjustment assists in the movement of the straw and chaff over the surface of the slats IO. In Fig. 2, the arrow shows the direction of the air stream with the slats IO in the adjusted, dotted line position.

Shown in Fig. 3 is a slightly modified form of the invention illustrated in Figs. 1 and 2. The slats 1D' are substantially the same as the slats l of Figs. 1 and 2, except for the provision of tongues 24 along the top portions l' of the slats |0'. The tongues 24 extend into the apertures 18' and move up and down therein upon adjustment of the slats W `around the axis of the rod 12'. This interlocking between the tongues 24 and the apertures IB' adds to the transverse rigidity of the sieve construction.

In Figs. 4 and 5 the slats shown in Fig. 3 have been modified by eliminating the flange 20' to define the adjustable apertures in the sieve by depending fingers 26 having reinforcing and stififening ribs 28 which are a continuation of ribs 30 in the top portions W' of the slats l. This form of the invention has the advantage of eliminating any tendency for straws to hair pin over the Vertical partitions defining the apertures IS and |8' of the other forms of the invention illustrated, Having thus described my invention, what I desire to secure by Letters Patent and claim is:

1. An adjustable sieve or the like comprising a plurality of elongated slats disposed in parallelism and adjustable upon parallel axes, each of said slats being substantially L-shaped in crosssection With one arm of such shape constituting a relatively solid upper surface portion having edge portions in parallel with the edge portions of adjacent slats and with the second arm of the shape apertured and downwardly angularly disposed as a depending tail portion, and means supporting the slats on parallel axes substantially coinciding with the angle between the top and tail' portions and with the edges of the top portions away from the tail portions swngably adjustable downwardly angularly below the plane of the surface of the sieve to uncover the apertured tail portions of adjacent slats, said slats by reason of which the upper surface portion of the adjacent v,1.0

slat co-acts, with the slats in the full open position.

3. In an adjustable sieve or the like, slat construction as deflned in claim 1, wherein said upper surface portlons each have tongue portions disposed along the longitudinal edge remote from the axs of adjustment oo-acting with said apertured portlons.

ERNEST G. WAITE. 

